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E/8                         ARMADILLOS AND SNAKES                         CHAP.
Mr. W. H. Hudson has described the way in which this Armadillo
will kill a snake by holding it down and literally sawing the
reptile in half by help of the sharp and serrated edges of the
carapace. Dasypus has a very short tail, which is shielded by
distinct rings near the base.
Tatusia, novetncincta, is a species with nine movable bands.
The genus has four teats ; the ears are near together. There are
no caeca and no azygos lobe to the lung. A species apparently
belonging to this genus, but described under the generic names of
Cryptophrcwtus and Praopus, is remarkable for the thick covering
of hair, not entirely wanting but usually thin in other Armadillos.
In this particular species the coat of hair is so thick as to
conceal the underlying plates of the carapace. The individual
hairs are stiff, and one inch and a half in length.1
The genus Xenurits contains several species, the best known of
which is inaptly named X. unicinctus. As a matter of fact? the
characteristic feature of the genus is the existence of twelve
or thirteen movable plates between the two ends of the body,
JT. unicinctiis has twelve dorsal and three lumbar vertebrae. This
Armadillo, known by the vernacular name of the Cabassou, has one
of the most modified hands that are found in the family. The first
two digits are slender and elongated; but are quite normal in the
number of their phalanges. In the remaining three digits the
metacarpal is short and broad, while the proximal phalanx is
either suppressed altogether or fused with the metacarpal, the
middle phalanx is present but short, while the third phalanx is very
large indeed. As in Dasypus, but not as in Tatusia, which is in
so many other respects divergent from these genera, the lungs
have an azygos lobe. As a small point of difference, tending to
show an alliance between the genera Xenurus and Dasypus
and their difference from T&tusia, is the deeply-imbedded gall-
bladder ; this sac is not nearly so deeply plunged into the hepatic
tissue in Tatusia. Xenurus has no caecal dilatations. ^ The
brain " is intermediate in its form and surface markings between
&asypus and Tolypeutes" The small intestine is nearly eighteen
times the length of the large. But these intestinal measurements
are not of much avail in this group as marks of affinity, since in
three species of Dosi/pus G-arrod gives the following widely-
divergent lengths:óD. villosus, 11*5 feet and 1~25 ; &. minutus
1 Flower, Proc. Zool* Soc. 1880, p. 419.